Fight the (tick) bite: Profile of doctoral student Meagan Vaughn

In what should be a relief to folks who work and play outdoors, a UNC-Chapel Hill doctoral student found out how to almost completely avoid tick bites.

Research by Meagan Vaughn, a doctoral student in epidemiology at the Gillings School of Global Public Health, found that some State of North Carolina outdoor workers reduced tick bites by 93 percent by wearing repellent-treated clothing patented by a Greensboro-based company.

Meagan Vaughn displays clothing worn by outdoor workers in a research study on prevention of tick bites. The clothing is impregnated with a long-lasting repellent and insecticide. Photo by Dan Sears.

The company, Insect Shield, uses a proprietary process to impregnate clothing with permethrin, a chemical with repellent and insecticidal properties. The clothing retains protection for more than 70 washes. For many, that’s a more efficient way of facing the outdoors and repelling ticks and other insects than a do-it-yourself application of permethrin to clothing. In that case, the clothing must be sprayed until saturated and dry completely before wearing. Then, it must be reapplied after several washings to maintain insecticidal properties, and is therefore underused by many outdoor workers.

“You can’t treat for ticks on the fly; you’ve got to do it ahead of time if you’re using permethrin. This clothing allows you to be ready to go outdoors,” Vaughn said.

Vaughn led a pilot study on the effectiveness of the clothing in preventing tick bites. Of the 16 study participants — outdoor workers from the N.C. Division of Water Quality — nine used permethrin-impregnated clothing and seven used standard preventive measures. All participants kept weekly tick bite logs between March and September, something that they already were doing. Workers wearing the permethrin-impregnated clothing had a 93 percent reduction in total tick bites compared to workers using standard tick bite prevention measures.

Tick-borne diseases are on the rise in North Carolina, and across the U.S. outdoor workers are at particular risk. Many people with outdoor occupations report multiple tick bites each year. Federal occupational safety recommendations advise outdoor workers to wear light-colored protective clothing, tuck pants into socks or boots, regularly apply repellent to skin and clothing, and check for ticks daily.

Vaughn said that some workers wrote stories on the backs of their tick logs about their experiences, and one even exclaimed that the clothing had “changed my life!”

“The results of the pilot study were so dramatic that we decided to submit a proposal for a larger study to see if the results would hold true in a randomized-controlled setting over several tick seasons,” Vaughn said.

Based on the pilot findings, Vaughn and faculty members Steven Meshnick, MD, PhD, professor of epidemiology in UNC’s public health school, and Charles Apperson, PhD, William Neal Reynolds Distinguished Professor Emeritus at N.C. State University, secured funding for a larger double-blind randomized study. The universities received a four-year, $1.1-million federal grant funded by the Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health.

“The technology holds the promise of a safe, simple and effective way to protect people from ticks and other insects,” Meshnick said. “If further studies show similar results, the apparel could be used by people who are often outdoors for work or recreation or both. I can envision many uses around the world, including in developing countries to prevent malaria spread by mosquitoes.”

Vaughn, Meshnick and Apperson are conducting research with more than 150 outdoor workers, including employees from the N.C. Forest Service, N.C. Parks and Recreation, and N.C. Wildlife Resources Commission. Because North Carolina bears a particularly large burden of tick-borne illnesses, the thousands of people who work in tick-infested areas could greatly benefit from the use of permethrin-impregnated clothing as part of standard occupational safety policies. Vaughn says that they plan to finish data collection in September 2012.

Vaughn was one of 22 recent recipients of the University’s Impact Award, an honor recognizing graduate student research that improves the life of people in North Carolina and beyond. The Graduate School, through the generosity of its Graduate Education Advancement Board members, sponsors the annual awards and recognizes recipients at a Graduate Student Recognition Celebration. She also received the public health school’s Marilyn and Al Tyroler Memorial Scholarship for the academic year 2011-2012.

Read about the pilot study published in the journal Vector-borne and Zoonotic Diseases.